Nitrogen fixation and reduction at boron

Boron learns to give back to nitrogen Although diatomic nitrogen is famously inert, a variety of transition metals can bind to it through a process termed backbonding. As the nitrogen weakly shares its own electrons, some electrons from the metal reach back out to it. Nonmetals would not seem to have the capacity for this type of bonding, but now Légaré et al. show that conventionally electron-deficient boron can be coaxed into it (see the Perspective by Broere and Holland). The authors treated boron-based precursors with potassium under a nitrogen atmosphere to produce several compounds with sandwiched dinitrogen between two boron centers in reduced motifs reminiscent of metal complexes. Science , this issue p. 896 ; see also p. 871